The present invention relates to an electrode needle, in particular for the treatment of parenchymatous tumours through radiofrequency-induced hyperthermy.
The treatment of tumoral masses through radiofrequency-induced hyperthermy has already been proposed with success. The instruments currently available for such treatment are catheter tubes with at least one terminal electrode, or needles with a rectilinear radiofrequency active filament.
However, catheter tubes are relatively large and, even though they are efficient due to the presence of a big electrode, they exhibit the disadvantage that they can only be introduced into the patient""s body up to the tumoral mass through natural open ways or ways opened through expansion.
On the other hand, needles with an active filament can be introduced into the body making them pass through the tissues, but they are limited in their action due to the small diameter of the active filament, which operates, on limited areas and thus implies longer operation and treatment times. On the other hand, if larger needles are use for the treatment of larger tumoral masses, the use of such needles is more traumatic for the patient.
The purpose of the finding is that of finding a remedy for the limitations of known instruments, thus providing a radiofrequency active electrode needle that could be used in the treatment of even considerable tumoral masses, maintaining in any case its limited diameter to reduce the traumatic effect and allow reaching organs or parts of organs that could not be otherwise reached with larger needles or tubes.
The purpose and resulting advantages are achieved with an instrument comprising a hollow guide needle and a radiofrequency active filament threaded, and sliding into, said needle between a retracted position, withdrawn into the needle, and a forward position emerging from the distal end of the needle and where said filament has a terminal segment bending in a helical or spiral shape when the filament is in the forward position.
Thanks to such helical and/or spiral arrangement of a terminal part, even though the active filament is very thin, it is capable of irradiating and thus treating a much larger surrounding area than the area of its section.
In other words, starting from a very thin guide needle and radiofrequency active filament, it is possible to easily treat tumoral masses that are at least as wide as the width of the helical or spiral part of the filament.
Further details of the finding will appear more clearly from the following description, made with reference to the attached indicative and nonlimiting drawings. In such drawings: